Abrasive slinging apparatus

ABSTRACT

Apparatus for abrasively treating relatively large areas such as the removal of rust in shipyard operations, consists of an abrasive slinging head mounted at one end of an abrasive supply conveyor which is pivoted on a horizontal axis to a turntable moveable around a vertical axis, the conveyor serving as a boom for the head and being relatively balanced on the turntable. A driving arrangement imparts oscillating motion to the conveyor and slinging head in either horizontal or vertical directions, or both, and enables the centerline of oscillation of the motion in either direction to be positioned as desired.

United States Patent [1 1 Yamanoto et a1.

[ ABRASIVE SLINGING APPARATUS [75] Inventors: Akira Yamanoto; Dan Yoshida;

Tatsumi Onaka; Minoru Shiraishi, all of Osaka, Japan [73] Assignee: Hitachi Shipbuilding and Engineering Company Ltd., Osaka, Japan [22] Filed: I June 27, 1972 21 Appl.'No.: 266,693

[30] Foreign Application Priority Data June 30, 1971 Japan 46/57168 [52] US. Cl. 51/9 [51] Int. Cl B24c 3/06, B240 7/00, B24c 3/32 [58] Field of Search ..5l/8,9, 12,180

[56] References Cited UNITED STATES PATENTS 3,566,543 3/1971 Fogle 51/9 Dec. 11, 1973 Schenck 51/8 Primary ExaminerD0nald G. Kelly Att0rneyFarley, Forster & Farley 57 ABSTRACT Apparatus for abrasively treating relatively large areas such as the removal of rust in shipyard operations, consists of an abrasive slinging head mounted at one end of an abrasive supply conveyor which is pivoted on a horizontal axis to a turntable moveable around a vertical axis, the conveyor sewing as a boom for the head and being relatively balanced on the turntable. A driving arrangement imparts oscillating motion to the conveyor and slinging head in either horizontal or vertical directions, or both, and enables the centerline of oscillation of the motion in either direction to be positioned as desired.

9 Claims, 10 Drawing Figures minimum 1 ma 377-1440 sum 10$ 4 PATENIEB DEC 1 1 I973- SHEET 2 OF 4 PATENTED DEC 1 1 I975 SHEET 3 0F 4 1 ABRASIVE SLINGING APPARATUS SUMMARY OF THE INVENTION The present invention relates to an abrasive slinging apparatus suitable for abrasively treating a relatively large area such as in rust removal operations in shipyards where the so-called sand or shot blast method has been employed. The object of the present invention is to provide such an abrasive slinging apparatus which is simple in construction and has an abrasive slinging head supported in a cantilever fashion on a base, and automatically oscillatable horizontally, vertically or in both of such directions.

An abrasive slinging apparatus according to the present invention comprises conveyor means, an abrasive slinging head connected to one end of the conveyor means, a drive motor for the head, and a conveyor driving motor installed at the other end of the conveyor means. The conveyor means is pivotally supported on a base between the head and conveyor driving motor and an abrasive inlet connection is provided on the conveyor means adjacent to the pivotal support thereof; and, drive means enables the conveyor means to be oscillated with a predetermined amplitude with respect to the base, the arrangement being such that an abrasive is fed from the inlet connection into the head by the conveyor means and is slung from the head as the head is oscillated.

With the apparatus of the invention, since the abrasive is not fed directly into the oscillating head but is supplied to the inlet connection disposed adjacent to the pivotal axis around which the conveyor means oscillates, abrasive can be easily supplied to the apparatus by means such as a flexible tube. Moreover, the conveyor means is also used as a lever or boom for supporting the head in a cantilever fashion, and the motor for driving the conveyor means is employed as a balance to counteract the weight of the head, resulting in an apparatus which is simple in construction and requires only a small amount of power for oscillating motion.

Preferably, the conveyor means is structurally connected with a cylindrical housing disposed parallel thereto and the motor for driving the head is mounted on one end of the cylindrical housing which is disposed oppositely to the head with respect to the base on which the conveyor is mounted, rotational power from the driving motor being transmitted to the head through a drive shaft extending through and journalled in the cylindrical housing. In this arrangement, the apparatus can be balanced more easily than in the case where the head driving motor is disposed on the head itself, thereby making it possible to decrease the power required for oscillating the head.

In the preferred embodiment of the present apparatus, a turntable is provided which is rotatable on the base around a vertical axis, and the conveyor means is supported on the turntable for rotation around a horizontal axis so that the conveyor means is movable both horizontally and vertically. Further, the drive means for oscillating the conveyor means is divided into two units, one for horizontal movement and the other for vertical movement.

By adapting the head to automatically oscillate both horizontally and vertically, efficient rust removal operations can be carried out without the need for frequent displacement of the base of the apparatus.

Other features and advantages of the present invention will be understood from the following description of the embodiments thereof illustrated in the accompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of an abrasive slinging apparatus constructed in accordance with the invention;

FIG. 2 is a plan view thereof;

FIG. 3 is an enlarged transverse sectional elevation of the abrasive slinging head portion of the apparatus;

FIG. 4 is an enlarged transverse sectional elevation showing the base and turntable portion of the apparatus;

FIG. 5 is an enlarged sectional detail showing the turntable drive means portion of the structure illustrated in FIG. 4;

FIG. 6 is a sectional plan view, partly schematic, of the drive means of FIG. 5;

FIG. 7 is an enlarged transverse sectional elevation through the horizontal pivot on which the conveyor means is mounted, illustrating the drive means for vertical motion;

FIG. 8 is an enlarged side elevation, partly schematic, of the drive means of FIG. 7;

FIG. 9 is a side elevation showing a modified form of the abrasive slinging end of the apparatus; and,

FIG. 10 is an end elevation showing another modified form of the abrasive slinging end of the apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIGS. 1 and 2, the apparatus includes a base 1 on which is mounted a turntable 2 adapted to be rotated around a vertical axis and carrying conveyor means 3 comprising a cylindrical casing 4 having an auger 5 rotatably supported therein. A conveyor drive motor 6 for driving the auger is connected directly to one end of the cylindrical casing 4, a delivery chute 7 projects downwardly from the other end of the casing 4, and an abrasive inlet connection 8 includes a transversely extending tubular member communicating with the upper side of the casing 4 and adapted to be connected to a flexible supply hose 9, as shown in phantom in FIG. 2.

The conveyor means 3 is structurally connected with a cylindrical housing 10 disposed substantially parallel thereto. A rotatable shaft 11 is coaxially disposed within the cylindrical housing 10 and a motor 12 for driving the shaft 11 is connected directly to the end of the housing 10 on the same side of the turntable as the conveyor drive motor is located. At the other end of the cylindrical housing 10, an abrasive slinging head 14 is laterally disposed through the intermediary of a bevel gear box 13 and the delivery chute 7 of the conveyor means 3 is connected to the central supply port of the head 14.

As shown in FIG. 3, the gear box 13 houses a transversely supported output shaft 17 driven from the rotatable shaft 11 within the cylindrical housing 10 through a pair of bevel gears l5, l6, and a sling impeller 18 in the head 14 is joined to the outer end of the output shaft 17. A casing 19 surrounding the impeller 18 is rotatable around the axis of the output shaft 17 with respect to said gear box 13, and a retaining ring 20 fitted in the casing 19 is adapted to be clamped against the gear box 13, so that the casing 19 can be fixed in position with a discharge opening 22 formed therein (see FIGS. 1 and 2) directed as desired. A rotatable junction 23 is also provided between the delivery chute 7 and the casing 19 so that these parts can be relatively moved around the axis of the output shaft 17. A distributor 24 is attached to the central portion of the impeller l8 and is surrounded by a control gauge 25 fixed to the casing 19. Abrasive from the delivery chute 7 passes through notches in the distributor rotating with the impeller 18, and then through an opening in the control gauge 25 so as to be fed between the blades of the impeller in timed relation and slung from the discharge opening 22 thereby.

The conveyor means 3 and the cylindrical housing 10 are connected together at one end through the gear box 13 and head 14 and also at a position below the abrasive inlet connection 8 of the conveyor means 3 by means of a connecting member 26 (FIG. 1) supported for vertical swinging motion on the upper end of the turntable 2 by means of a transverse shaft 27.

As shown in FIGS. 4 through 6, horizontal motion drive means 28 are provided in the base 1 and are constructed as follows.

A tubular shaft 29 fixed to the lower side of the turntable 2 is composed of two shaft portions, an upper portion 29a and a lower portion 29b. A bearing retainer 30 is fixed to the upper surface of the base 1 coaxially with the shaft 29 and the turntable 2 is rotatably supported on the base 1 through a tapered roller bearing 31 interposed between the bearing retainer 30 and the upper portion 29a of the shaft 29 and held in position by a nut 32'screwed onto the shaft. A driven wheel assembly 33 is secured by bolts 39 to a shoulder on the upper shaft portion 29a and is coaxially fitted over the lower portion 29b of the shaft 29. This driven wheel assembly 33 comprises a sprocket 34 sandwiched between two discs 37 and 38 through linings 35 and 36 with a predetermined pressure applied by an elastic plate 40 secured to the disc 37 by bolts 41. When a torque exceeding the predetermined value is applied, the sprocket 34 will idly rotate between the discs 37 and 38 to interrupt frictional power transmission therebetween, and the holding pressure can be adjusted by the bolts 41. A rotatable support 42 located under the driven wheel assembly 33, is fitted over the lower shaft portion 29b on bearings 43 and 44 and is held in position by a bolt 53 and a plate 54. Drive means 45 for oscillating the rotatable support 42 includes a motor 46 mounted on a bracket 56 secured to the base 1 by bolts 53 and having a crank arm 47 connected to one end of the support 42 by a link 48 and connecting pins 57. Further, a motor 49 for rotating the driven wheel assembly 33 to rotate the turntable 2 is attached to a bracket 55 at the other end of the support 42 and is connected to the assembly 33 by a chain 50 entrained around a sprocket 52 secured to the shaft 51 of the motor 49 and around the sprocket 34 of the driven wheel assembly 33. It is to be understood that the motor 49 is capable of transmitting the oscillating motion of the support 42 through the chain 50, and is, for example, a fluid pressure actuated type of motor so that in the case of torque transmission from the chain 50, the motor shaft 51 cannot be rotated around its own axis.

In the arrangement described above, when the motor 46 is rotated, the support 42 is oscillated around the axis of the shaft 29 with a predetermined amplitude by the link 48 in accordance with the rotation of the crank arm 47. At this time, since the shaft 51 of the motor 49 attached to the support 42 is not rotated, the aforesaid oscillating motion is transmitted from the sprocket 52 through the chain 50 to the sprocket 34 of the driven wheel assembly 33, thereby causing horizontal oscillating motion of the turntable 2 with a predetermined amplitude. Therefore, the conveyor means 3, the cylindrical housing 10 and the head 14 unitarily execute horizontal oscillating motion with a predetermined amplitude.

When it is desired to change the direction of the amplitude centerline of the oscillating motion, the motor 49 is actuated to rotate the driven wheel assembly 33 by the wrapping connector driving system of the sprockets 52, 34 and the chain 50, through a required angle. This operation for changing the direction of amplitude centerline of the oscillating motion can be effected during the oscillating motion of the head 14 etc., as well as during the stoppage thereof.

Vertical motion drive means 81 will now be described with reference to FIGS. 4, 7 and 8.

The turntable 2 is bifurcated at its upper portion to receive the cylindrical housing 10 therebetween. The transverse shaft 27 supporting the connecting member 26 is supported on the upper portion of the turntable 2 by two ball bearings 58, and the member 26 is supported on the shaft 27 through ball bearings 59 located between the ball bearing 58. A driven wheel assembly 60 is attached to one end of the transverse shaft 27, and, the assembly 60, like the driven wheel assembly 33 shown in FIG. 5, comprises a sprocket 61 sandwiched between two discs 64 and 65 and linings 62 and 63 with a predetermined pressure applied through an elastic plate 66 secured to the disc 65 by bolts 67. When a torque exceeding the predetermined pressure set by adjusting the tightening of the bolts 67 is applied, the sprocket 61 will idly rotate between the discs 64 and 65 to interrupt frictional power transmission therebetween. An inclination angle change arm 69 is attached to the disc 65 by bolts 68. Means 70 are provided for changing the position of the arm 69 and comprise the driven wheel assembly 60, a motor 72 attached to the turntable 2 through a bracket 71, a sprocket 73 fixed to the shaft of the motor 72, and a chain 74 entrained around the sprocket 73 and the sprocket 61 of the driven wheel assembly 60. An oscillation drive motor 75 is attached to the cylindrical housing 10 (see FIG. 1), and a crank arm 76 fixed to the shaft 77 of the motor 75 is connected to the inclination angle change arm 69 by a link 78 and connecting pins 79 and 80. In addition, the motors 72 and 75, like the motor 49 shown in FIG. 5, cannot have their shafts 71 rotated in the case of torque transmission from the outside: They may, e.g., be fluid pressure actuated type motors.

In the arrangement described above, when the crank arm 76 is rotated by the motor 75 with the inclination angle change arm 69 set in a suitable angular position around the transverse shaft 27, the motor shaft 77 around which the crank 76 is rotated is vertically displaced relative to the transverse shaft 27 because of the arm 69 being in its fixed state. Therefore, the head 14, the conveyor means 3 and the cylindrical housing 10 can be unitarily oscillated with a predetermined amplitude around the transverse shaft 27 in a vertical direction.

When it is desired to change the direction of the amplitude centerline of the vertical oscillating motion, the

inclination angle change motor 72 is rotated to rotate the driven wheel assembly 60 through a predetermined angle. That is, the angle at which the inclination angle change arm 69 is set around the transverse shaft 27 is adjusted to change the level of the connecting pin 79. This operation for changing the position of the centerline of vertical oscillation may be effected during the oscillating motion of the head 14, etc. as well as during the stoppage thereof.

In a rust removing operation, the conveyor drive motor 6 is driven to rotate the auger 5, while the sling head drive motor 12 is driven to rotate the impeller 18 of the head 14 through the rotatable shaft 17 and a pair of bevel gears 15 and 16. In such condition, if an abrasive material is fed into the inlet connection 8 through the flexible supply hose 9, the abrasive is passed toward the head 14 by the auger 5 and fed into the head 14 through the delivery chute 7, whereupon it is slung outwardly of the head 14 by the impeller 18 through the discharge opening 22. In this case, the motor 49 of the horizontal motion drive means 28 for rotating the turntable 2, and the motor 72 of the vertical motion drive means 81 for changing the position of the arm 69 are actuated in advance to displace the head 14 to a desired position; and, the motor 46 of the means 28 and- /or the motor 75 of the means 81 is also actuated whereby the head 14 for slinging the abrasive can be automatically oscillated horizontally and/or vertically around said preset position with a predetermined amplitude. Thus, the abrasively treated region can be covered in accordance with the location of the rust to be removed. In addition, instead of mounting the base 1 on the ground, it may be installed on a vertically displaceable support carried, for example, on a working vehicle.

In the embodiment described above both horizontal and vertical motion drive means 28 and 81 are provided, but only one of them'may be present.

Further, besides fluid pressure-actuated type motors including air motors, geared head motors using worm gears may be employed as the motors 49 and 72. It is also possible to utilize fluid pressure cylinder means instead of the reciprocating drive means using a motor and crank arm.

FIG. 9 shows an example in which the impeller 18 of the head 14 is connected directly to the rotatable shaft 11 in the cylindrical housing 10. FIG. shows an example in which the cylindrical housing 10 is omitted so that the head 14 is supported only by the conveyor means 3 and the drive motor 12 is attached directly to the head 14.

We claim: I

1. An abrasive slinging apparatus comprising conveyor means, an abrasive slinging head connected to one end of said conveyor means, a drive motor for said head, a conveyor driving motor installed at the other end of said conveyor means, a base, means for pivotally supporting said conveyor means on said base between said head and said conveyor driving motor, an abrasive inlet connection provided on said conveyor means adjacent the position where said conveyor means is supported on the base, and drive means for repeatedly oscillating said conveyor means with a predetermined amplitude with respect to said base, the arrangement being such that an abrasive from said inlet connection is fed into the head by said conveyor means and is slung from said head which executes oscillating motion.

' 2. An abrasive slinging apparatus as set forth in claim 1, wherein said conveyor means is provided with a cylindrical housing disposed substantially parallel therewith, said head drive motor is mounted on one end of said cylindrical housing which is disposed oppositely to said head with respect to the base, and the turning force of said head drive motor is transmitted to the head through a drive shaft supported in said cylindrical housing.

3. An abrasive slinging apparatus as set forth in claim 1 wherein the means pivotally supporting the conveyor means includes a turntable mounted on the base for rotation around a vertical axis, said drive means for oscillating said conveyor means being operatively connected to the turntable.

4. An abrasive slinging apparatus as set forth in claim 3 wherein said drive means comprises a driven wheel coaxially attached to said turntable, a rotatable support mounted coaxially with said driven wheel, a driven wheel driving motor mounted on the rotatable support, means for transmitting power from said driven wheel driving motor to the driven wheel, and a drive motor mounted on the base for oscillating said rotatable support, the arrangement-being such that the oscillating motion of the rotatable support is transmitted to the turntable through the means for transmitting power from said driven wheel driving motor to the driven wheel and through said driven wheel, the direction of the centerline of the oscillating motion being changeable by actuation of the driven wheel driving motor.

5. An abrasive slinging apparatus as set forth in claim 1 wherein the means pivotally supporting said conveyor means includes pivot means mounting said conveyor means for vertical swinging movement around a horizontal axis, said driven means for repeatedly oscillating said conveyor means being operatively connected thereto.

6. An abrasive slinging apparatus as set forth in claim 5 wherein the drive means for oscillating the conveyor means comprises an arm supported coaxially with the axis of the pivot means, means for changing the position of said arm, and a driven motor operatively connected to said arm, the arrangement being such that the direction of the centerline of vertical oscillating motion of the conveyor means can be changed by changing the position of said arm.

7. An abrasive slinging apparatus as set forth in claim 1 wherein the means pivotally supporting said conveyor means includes a turntable mounted on said base for movement around a vertical axis, and pivot means mounting said conveyor means on said turntable for vertical swinging movement around a horizontal axis, said drive means being divided into two units, one for horizontal movement and the other for vertical movement.

8. An abrasive slinging apparatus as set forth in claim 7, wherein said drive means for horizontal movement comprises a driven wheel coaxially attached to said turntable, a rotatable support mounted coaxially with said driven wheel, a driven wheel driving motor mounted on the rotatable support, means for transmitting power from said driven wheel driving motor to the driven wheel and a drive motor for repeatedly oscillating said rotatable support through a crank mechanism, the arrangement being such that the oscillating motion of the rotatable support is transmitted to the turntable through the means for transmitting power from said able with respect to the turntable, means for changing the position of said arm, and a drive motor operatively connected to said arm through a crank mechanism, the arrangement being such that the direction of the amplitude centerline of vertical oscillating motion of the conveyor means can be changed by changing the position of said arm. 

1. An abrasive slinging apparatus comprising conveyor means, an abrasive slinging head connected to one end of said conveyor means, a drive motor for said head, a conveyor driving motor installed at the other end of said conveyor means, a base, means for pivotally supporting said conveyor means on said base between said head and said conveyor driving motor, an abrasive inlet connection provided on said conveyor means adjacent the position where said conveyor means is supported on the base, and drive means for repeatedly oscillating said conveyor means with a predetermined amplitude with respect to said base, the arrangement being such that an abrasive from said inlet connection is fed into the head by said conveyor means and is slung from said head which executes oscillating motion.
 2. An abrasive slinging apparatus as set forth in claim 1, wherein said conveyor means is provided with a cylindrical housing disposed substantially parallel therewith, said head drive motor is mounted on one end of said cylindrical housing which is disposed oppositely to said head with respect to the base, and the turning force of said head drive motor is transmitted to the head through a drive shaft supported in said cylindrical housing.
 3. An abrasive slinging apparatus as set forth in claim 1 wherein the means pivotally supporting the conveyor means includes a turntable mounted on the base for rotation around a vertical axis, said drive means for oscillating said conveyor means being operatively connected to the turntable.
 4. An abrasive slinging apparatus as set forth in claim 3 wherein said drive means comprises a driven wheel coaxially attached to said turntable, a rotatable support mounted coaxially with said driven wheel, a driven wheel driving motor mounted on the rotatable support, means for transmitting power from said driven wheel driving motor to the driven wheel, and a drive motor mounted on the base for oscillating said rotatable support, the arrangement being such that the oscillating motion of the rotatable support is transmitted to the turntable through the means for transmitting power from said driven wheel driving motor to the driven wheel and through said driven wheel, the direction of the centerline of the oscillating motion being changeable by actuation of the driven wheel driving motor.
 5. An abrasive slinging apparatus as set forth in claim 1 wherein the means pivotally supporting said conveyor means includes pivot means mounting said conveyor means for vertical swinging movement around a horizontal axis, said driven means for repeatedly oscillating said conveyor meanS being operatively connected thereto.
 6. An abrasive slinging apparatus as set forth in claim 5 wherein the drive means for oscillating the conveyor means comprises an arm supported coaxially with the axis of the pivot means, means for changing the position of said arm, and a driven motor operatively connected to said arm, the arrangement being such that the direction of the centerline of vertical oscillating motion of the conveyor means can be changed by changing the position of said arm.
 7. An abrasive slinging apparatus as set forth in claim 1 wherein the means pivotally supporting said conveyor means includes a turntable mounted on said base for movement around a vertical axis, and pivot means mounting said conveyor means on said turntable for vertical swinging movement around a horizontal axis, said drive means being divided into two units, one for horizontal movement and the other for vertical movement.
 8. An abrasive slinging apparatus as set forth in claim 7, wherein said drive means for horizontal movement comprises a driven wheel coaxially attached to said turntable, a rotatable support mounted coaxially with said driven wheel, a driven wheel driving motor mounted on the rotatable support, means for transmitting power from said driven wheel driving motor to the driven wheel and a drive motor for repeatedly oscillating said rotatable support through a crank mechanism, the arrangement being such that the oscillating motion of the rotatable support is transmitted to the turntable through the means for transmitting power from said driven wheel driving motor to the driven wheel and through said driven wheel, the direction of the amplitude centerline of the oscillating motion being changeable by actuation of the driven wheel driving motor.
 9. An abrasive slinging apparatus as set forth in claim 7, wherein the drive means for vertical movement comprises an arm supported coaxially with the axis of the pivot means around which the conveyor means is movable with respect to the turntable, means for changing the position of said arm, and a drive motor operatively connected to said arm through a crank mechanism, the arrangement being such that the direction of the amplitude centerline of vertical oscillating motion of the conveyor means can be changed by changing the position of said arm. 